Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
  • B62D—MOTOR VEHICLES; TRAILERS
  • B62D1/00—Steering controls, i.e. means for initiating a change of direction of the vehicle
  • B62D1/02—Steering controls, i.e. means for initiating a change of direction of the vehicle vehicle-mounted
  • B62D1/04—Hand wheels
  • B62D1/06—Rims, e.g. with heating means; Rim covers
  • B62D1/065—Steering wheels with heating and ventilating means
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
  • B62D—MOTOR VEHICLES; TRAILERS
  • B62D1/00—Steering controls, i.e. means for initiating a change of direction of the vehicle
  • B62D1/02—Steering controls, i.e. means for initiating a change of direction of the vehicle vehicle-mounted
  • B62D1/04—Hand wheels
  • B62D1/046—Adaptations on rotatable parts of the steering wheel for accommodation of switches
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
  • H05B1/00—Details of electric heating devices
  • H05B1/02—Automatic switching arrangements specially adapted to apparatus ; Control of heating devices
  • H05B1/0227—Applications
  • H05B1/023—Industrial applications
  • H05B1/0236—Industrial applications for vehicles

Definitions

• the invention relates to a device for heating a steering wheel and for detecting a steering wheel contact.
• the invention further relates to a method for heating a steering wheel and for detecting a steering wheel contact.
• Touch recognition systems with sensors are available which can detect whether or not the driver has the hand or other body parts on the steering wheel.
• a combination of both systems is difficult because they can affect each other electrically.
• a steering wheel is known in which an integrated into the steering wheel rim hand touch sensor system is shielded by applying a voltage to a shielding mat from the metallic steering wheel skeleton.
• Steering wheel heating is also integrated into the steering wheel.
• the structure of the steering wheel rim provides the following sequence of layers (from inside to outside): Skeleton - Foaming - Heating mat - Shielding mat - Sensor mat - Case.
• the sensor mat, the shield mat, and the heater mat include one or more scan loops that define respective scan zones. Thanks to the zoning, the heating can be limited to those areas of the steering wheel rim where a hand touch has been detected.
• the heating mat at the same time as a shielding mat, so that can be dispensed with a separate shielding mat.
• the heating mode and the hand touch detection are performed alternately in very short time intervals with a respective period of about 10 to 50 milliseconds. While the heating current for the heating mat can be about 4 to 8 amperes, the shielding current is less than 200 Microampere provided.
• the heating current and the shielding current may be provided by the same or different current sources. Close juxtaposed electrical lines of the hand touch sensor system are isolated and additionally surrounded by a shield so that the transmitted signals do not interfere with each other.
• the object of the invention is to provide a simple design and therefore cost-effective device with both a steering wheel heated and steering wheel touch can be reliably detected.
• the device according to the invention serves both for heating a steering wheel and for detecting a steering wheel contact and comprises a steering wheel skeleton made of an electrically conductive material and an electrical heating conductor arranged outside the steering wheel skeleton.
• the device according to the invention further comprises a control and evaluation device connected to the steering wheel skeleton and the electrical heating conductor, by means of which the electrical heating conductor is repeatedly operated temporarily as a heating element for heating the steering wheel in a heating mode and temporarily as a sensor element for detecting a steering wheel contact in a measuring operation.
• the control and evaluation device is set up such that it holds the steering wheel skeleton at a predetermined, in particular constant potential, at least during each measuring operation.
• the invention is based on the finding that an electrically "reassured" steering wheel skeleton does not interfere with the measuring operation for detecting steering wheel touch. ⁇ br/> ⁇ br/>
• the influence of the steering wheel skeleton is constant over time and can therefore be taken into account (“calculated out") as a defined variable in the measurements. become.
• a significant advantage of this measure according to the invention over the solutions known from the prior art is that there is no longer any need to shield the or the electrical conductors required for the heating and measuring operation as well as their supply lines with respect to the steering wheel skeleton.
• the steering wheel skeleton can be kept at the predetermined potential in particular via an RCL element, wherein it is not absolutely necessary for the RCL element to have three components (inductance, capacitor and resistance).
• an electrically conductive shield connected to the control and evaluation device is arranged in an advantageous embodiment outside the electrical heating conductor.
• the shield according to the invention is not a passive shield in the traditional sense, which is grounded. Instead, the control and evaluation device is set up in such a way that it applies a time-varying voltage to the shield during each measuring operation. The varying field generated by the actively operated shield enters the measurements as a defined reference variable, thus providing better and more reliable results.
• the shield can be laid according to a specification to different, predetermined, defined potentials, wherein the control and evaluation device is set up accordingly.
• the shield can also actively compensate for certain currently detected influences in order to obtain clearer signals during the measurements.
• the control and evaluation device is set up so that it adapts the time intervals in which the electrical heating conductor is operated in the measuring mode and in the heating mode, dynamically taking into account current parameters, which are fed repeatedly to the control and evaluation. These parameters reflect current conditions such as the current steering wheel temperature or certain traffic situations, etc. In certain circumstances, it may e.g. make sense to switch between heating and measuring mode faster or slower or to extend or shorten the intervals of one of the two operating modes relative to those of the other operating mode.
• the electrical heating conductor may be inserted in the form of a mat in the steering wheel.
• the heating element can also be introduced as a single wire into the steering wheel by means of a special working method, which itself is not the subject of the present invention.
• the invention also provides a method for heating a steering wheel and for detecting a steering wheel contact, wherein the steering wheel has a steering wheel skeleton of an electrically conductive material and an electrical heating conductor arranged outside the steering wheel skeleton, which are both connected to a control and evaluation device.
• the inventive method comprises the following step: operating the electric heating element alternately in a heating operation as a heating element for heating the steering wheel and in a measuring operation as a sensor element for detecting a steering wheel touch, wherein the steering wheel skeleton is held at least during each measuring operation at a predetermined, in particular constant potential.
• a voltage which varies over time is applied to an electrically conductive shield arranged outside the electrical heating conductor and connected to the control and evaluation device during each measuring operation.
• the shield can be laid according to a specification to different, previously defined, defined potentials, or the shield can actively compensate for certain currently recognized influences in order to obtain clearer signals in the measurements.
• the inventive method according to the embodiment of the invention each dynamically adjust taking into account current parameters that are supplied to the control and evaluation repeatedly.
• the steering wheel rim has inside a steering wheel skeleton 10 made of an electrically conductive material. Outside the steering wheel skeleton 10, an electrical heating conductor 12 is arranged.
• the electrical heating conductor 12 is inserted for example in the form of a mat in the steering wheel rim, but can also be introduced by means of a special work process as a single wire in the steering wheel rim.
• an optional, electrically conductive shield 14 is arranged outside the heat conductor 12.
• the outermost layer of the steering wheel rim is a shell 16.
• the steering wheel rim may include further layers.
• the steering wheel skeleton 10, the heating conductor 12 and optionally the shield 14 are connected to a control and evaluation device 18, which may be formed as a central unit or in the form of a plurality of individual units.
• the steering wheel can be heated on the one hand.
• the device also serves to detect a steering wheel touch.
• the electrical heating element 12 has a dual function as a heating element and as a sensor element.
• the electrical heating element 12 is operated repeatedly at times in a heating operation as a heating element for heating the steering wheel and temporarily in a measuring operation as a sensor element for detecting a steering wheel contact.
• control and evaluation is set up so that it holds the steering wheel skeleton 10 at least during each measuring operation at a predetermined, in particular constant potential.
• the steering wheel skeleton 10 is thus electrically “calmed down” so that it does not interfere with the measuring operation for detecting steering wheel touch.
• the steering wheel skeleton 10 is held for this purpose during the measuring operation intervals at a predetermined potential, preferably from an RCL member (not shown).
• a predetermined potential preferably from an RCL member (not shown).
• the shield 14 is not a passive shield that is grounded only.
• the control and evaluation device 18 applies a time varying voltage to the shield 14 during each measurement operation.
• the varying field generated by the actively operated shield 14 is included as a defined reference in the measurements, thereby providing better and more reliable results.
• the shield 14 can, in accordance with a specification from the control and evaluation device 18, be set to various, predetermined potentials be placed.
• the shield 14 may also actively compensate for certain currently detected influences to enable more robust signals in the measurements.
• the electric heating element 12 and optionally the shield 14 Apart from the steering wheel skeleton 10, the electric heating element 12 and optionally the shield 14, the steering wheel rim for the heating or measuring operation on no further electrically controlled layer.
• the control and evaluation device 18 ensures that the time intervals in which the electrical heating conductor 12 is operated in the measuring mode and in the heating mode, each dynamically adjusted taking into account current parameters.
• the corresponding parameter values such as the currently achieved steering wheel temperature or certain traffic situations, etc., enable an assessment of the current conditions and are repeatedly supplied to the control and evaluation device 18.

Landscapes

• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Transportation (AREA)
• Mechanical Engineering (AREA)
• Steering Controls (AREA)
• Air-Conditioning For Vehicles (AREA)

Priority Applications (5)

Applications Claiming Priority (2)

Publications (1)

Family

ID=59295222

Family Applications (1)

Country Status (7)

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Citations (4)

Family Cites Families (7)

• 2016
  • 2016-07-07 DE DE102016008243.7A patent/DE102016008243A1/de not_active Withdrawn
• 2017
  • 2017-07-06 KR KR1020197000353A patent/KR20190026741A/ko unknown
  • 2017-07-06 CN CN201780041653.6A patent/CN109415077B/zh active Active
  • 2017-07-06 US US16/311,730 patent/US11192570B2/en active Active
  • 2017-07-06 EP EP17736670.5A patent/EP3481696B1/de active Active
  • 2017-07-06 JP JP2019500473A patent/JP6892913B2/ja active Active
  • 2017-07-06 WO PCT/EP2017/066935 patent/WO2018007523A1/de unknown

Patent Citations (5)

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